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                                                                   March 5, 1996
 
SECURITIES AND EXCHANGE COMMISSION
450 Fifth Street N.W.
Washington, D.C. 20549
 
Re: Arthur J. Gallagher & Co.
  Registration Statement on Form S-1
 
Gentlemen:
 
  I am counsel for Arthur J. Gallagher & Co. (the "Company") in connection with
the above referenced Registration Statement on Form S-1 (the "Registration
Statement") relating to the registration for possible sale by the Company of
500,000 shares of the Company's common stock, par value $1.00 per share
("Common Stock"), in connection with future acquisitions (the Prospectus
included in the Registration Statement also relates to shares previously
registered on the Company's Registration Statement Nos. 33-60660, 33-76778 and
33-58101).
 
  In this connection, I have examined the originals or copies identified to my
satisfaction of such documents, corporate and other records, certificates, and
other papers as I deemed necessary to examine for purposes of this opinion.
 
  Based upon such examination, I am of the opinion that the shares of Common
Stock which may be sold by the Company, upon payment of the purchase price
therefor, will be duly and legally authorized and issued, fully paid and
nonassessable.
 
  I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and the reference to me under "Legal Opinion" in the
Prospectus included in this Registration Statement.
 
                                          Very truly yours,
                                          /s/ Carl E. Fasig
                                          -------------------------------------
                                          CARL E. FASIG
                                          Counsel and Secretary
 
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